Railroad track rails are subject to wear by the passage of trains over the rails. In particular, depressions in the upper surface of a rail may develop such that the railhead presents an undulating, corrugated surface. Moreover, the rail may develop burrs, or otherwise lose its symmetrical profile. Maintenance of smooth running surfaces on railroad track rails is important for reasons of safety, riding comfort, protection of the track, track bed and rolling stock, noise suppression, and reduced maintenance of the track and track bed.
Railroad switches and road crossings present particular problems to the rail grinding process. Gaps are necessarily presented in the railroad switches to permit the wheels of a railroad car to cross over one or the other of a set of rails in the switch, and at least one of the sets of rails in a switch will be curved. An additional problem presented at road crossings as well as at railroad switches, is the presence of obstructions close to the railhead. In short, rail grinding is a demanding, precise process, that even on straight, unobstructed, main line track is technically challenging, and which is particularly difficult at track intersections and road crossings.
The length of track sections at railroad switches and road crossings is typically short. Nevertheless, undulations in the rail surfaces of switches and crossings can impart vibratory motion to rolling stock, that will continue long after the train has passed by the switch or crossing. A railroad grinding machine particularly adapted for grinding the surfaces of railroad track rails at railroad switches and road crossings would accordingly be a decided advantage.